During recent years, pickup trucks have gained popularity as a form of family transportation as they are able to transport both passengers and cargo. If the truck is being used to carry cargo, truck bed liners are often installed to protect the metal surfaces of the truck bed from scratches and dents which may lead to rust and which affect the aesthetic appearance of the bed. Some liners, as disclosed in U.S. Pat. No. 4,162,098, protect only the floor of the truck bed; some, as disclosed in U.S. Pat. No. 4,245,863, protect only the side walls of the bed; and most protect the floor, the end wall, both side walls, and the tailgate. Various materials such as wood (U.S. Pat. No. 4,505,508), vinyl (U.S. Pat. No. 4,279,439), and plastic (U.S. Pat. No. 4,693,507), are used in the manufacture of truck bed liners, and some, such as those disclosed in U.S. Pat. Nos. 4,505,508, 4,893,862, 4,944,612 and 4,986,590, are multi-piece liners, while most have a unibody construction. The most common truck bed liner is made of a plastic material formed for a custom fit of various makes and models of pickup trucks. For example, the liner disclosed in U.S. Pat. No. 4,693,507 includes protection of the tailgate in its unitary construction, while the liners disclosed in U.S. Pat. Nos. 3,814,473, 4,047,749 and 4,111,481 and 4,958,876 use a separate liner to protect the tailgate.
The bed of the truck may also be used for the attachment of a camper top or cap in addition to carrying cargo in the open truck bed. To accommodate both uses, some liners, such as those disclosed in U.S. Pat. Nos. 4,681,360, 4,768,822 and 4,824,158, are used together with a camper top, and the truck bed liner disclosed in U.S. Pat. No. 4,875,731 is used as a bed liner or inverted and also used as a camper top.
The wide variety of truck bed liners available for a multitude of truck makes and models are able to sufficiently protect the truck bed from scratches and dents that could be created by carrying cargo in the bed, and many may be used with a camper top or cap to provide the owner with versatility in the use of the truck. However, the size and shape of the cargo may pose difficulties and transporting some items. Thus, tie-down fasteners, fasteners to which a rope, bungee cord or the like may be secured to hold oddly shaped or small items in place in the truck bed when being transported are desirable.
Many fasteners used in conjunction with truck bed liners are comprised of screws, bolts or the like. For example, chrome tie-down fasteners are screwed into the truck bed liner and in some instances assist in securing the liner to the truck. U.S. Pat. No. 4,648,765 discloses a fastener comprising a bracket and a ring wherein the bracket is screwed into the vehicle. Such tie-down fasteners must be separately installed by the consumer and often result in moisture damage of the truck bed by requiring the liner to be punctured or drilled by the consumer, and subsequent leakage or rain through the holes, where it becomes trapped between the liner and the truck bed damages the bed. It is therefore desirable to provide tie-down fasteners which do not need to be separately installed and which reduce the possibility of moisture damage to the truck. It is also desirable to provide tie-down fasteners which may be used on the sides, the front, and the floor of a truck bed liner, the lined or formed surfaces of a "topper" (camper top, cap or shell) and the lined or formed surfaces of a cargo bed cover. In their simplest form, toppers are usually attached to a vehicle cargo bed and may be comprised of a plastic form. Alternately, a topper may comprise an outer shell and an interior formed liner. A cargo cover may also be made of a formed plastic to enclose the vehicle's cargo bed. For both toppers and cargo covers, the provision of tie-down fasteners thereon provides flexibility to the consumer as to items which may be secured to the topper or cargo cover.
Many truck bed liners, whether or not they are of unitary construction, provide a rail guard which protects the top surface of the trucks side walls. For example, the truck bed liner disclosed in U.S. Pat. No. 4,333,678 includes rail guards which mount on top of the truck's side walls. Such rail guards are primarily used to protect the top of the truck's side walls and do not provide a means by which a tie-down may be fastened.
Rails extending above the truck's side walls which have holes therein for the attachment of tie-downs are currently available. Some of these rails, such as the Silver Falcon rails manufactured by D & G Products of Mt. Juliet, Tenn. and the rails disclosed in U.S. Pat. No. 4,936,724 can be used in conjunction with a unibody truck bed liner but are separate from the liner. Therefore, the consumer must install the rails in addition to the truck bed liner. Thus, it is desirable to provide rails which may be used for the attachment of tie-downs which are an integral part of a unibody truck bed liner.
A combination truck bed liner and camper top is disclosed in U.S. Pat. No. 4,875,731. In one embodiment of this invention, when the liner is in the orientation which results in a truck bed liner, rails which are an integral part of the liner extend above the top of the side walls of the truck. However, because these rails serve to attach the liner to the side walls of the truck when inverted to result in a camper top, the rails reside within the interior dimensions of the truck bed liner. Such an orientation results in stress on the side walls of the liner when tie-downs are attached to the rails. It is desirable to provide integral rails which reduce the amount of stress applied to the liner side walls and which provide additional strength to the rails in their use for attachment of tie-downs.